1. Field of the Invention
The present invention concerns a golf putter and more particularly a golf putter, in which the weight and center of gravity of the putter head is adjustable.
2. Description of the Related Art
Putting in golf is where the player hits the ball on a green toward a cup (hole) with a golf putter (called “putter” hereinafter), which requires a subtle touch in order to secure the exact distance and direction on greens that can have different turf orientation and/or undulation.
With putters, various factors come into transmitting exact subtle force adjustments of the player to the ball and especially with the head, it is said that the weight, position of the center of gravity, shape and hardness of the face are all important factors.
Of these factors, the weight and position of the center of gravity are said to be particularly important, because the former has a large impact on the driving force of balls and the latter on torsion resistance and the stroke orbit during impact.
However, individual players must make adjustments for the feel of the weight and center of gravity of a head 93 of an ordinary putter 90 as shown in FIG. 10, because they are set presupposing they are for use by the average player.
For instance, of well-known adjustment methods, a method exists where a weight such as a plumb plate or plumb tape is fixed to an area of a head 93, apart from a face 94, such as a tail 97 or a back 98.
Also, with regard to inventions concerning adjustment method, there has been proposed a method of adjustment, in which a weight is moved at will along a slot provided in the putter head (refer to Patent Document 1).
As shown in FIG. 11, this invention consists of adjusting the center of gravity of a head 100 by a moving weight 103 that has been inserted from a weight insertion port 102 and along a slide slot 101 provided in the bottom rear of the head 100 and then fixing it in place in the appropriate position.
However, in the aforementioned method of attaching a plumb plate or tape, the range of adjustment is too limited because the mass of the plumb plate, for example, is too small compared to that of the head. In addition, they can come off during play, and hence violate the rule prescribing that club performance must remain unchanged throughout play.
With regard to the invention disclosed in Patent Document 1, not only the range of adjustment was too limited because the mass of the weight is smaller than that of the head but also the mass needs to be removed and fixed in place using a tool, thus preventing subtle adjustments to be easily carried out.
Patent Document 1: Publication of Registered Utility Model No. 3109501